Thai Investigators Review New Blast Video

The next Thai national police chief Chakthip Chaijinda (L) talks with Thai national police chief Somyot Pumpanmuang (R) during a religious ceremony near the Erawan shrine, the site of Monday's deadly blast, in central Bangkok, Thailand, August 21, 2015.

Thai authorities say they are investigating new security camera footage that could help the investigation into last week's deadly bomb blast at a Bangkok shrine.

The surveillance video is related to a separate attack that occurred hours after and several kilometers away from the shrine blast. The closed circuit television footage shows a man in a blue shirt placing a bag on the ground and kicking it off a footbridge and into the water, near where the second explosion later occurred.

The second blast injured no one, but further rattled Bangkok residents. Officials have not been able to determine if the two incidents were related. But Thai police spokesman Prawuth Thawornsiri says police are seeking the man in the video for questioning.

Workers build a dam from sandbags as they attempt to seal off a canal to search for remnants of an explosive device that was thrown into the canal on Tuesday in Bangkok,Thailand, Aug. 19, 2015.

No arrests

Five days after the shrine attack, no arrests have been made, though investigators insist they are making progress. Police have issued an arrest warrant and released a sketch of a slender, young, allegedly foreign man with straggly hair and round glasses. They say he is the prime suspect.

The suspect was seen in closed circuit television footage leaving a backpack on a bench outside the Hindu shrine and walking away, shortly before the explosion, which killed at least 22 people. Officials believe he had help in planning the attack, but have expressed doubt it is connected to international terrorist groups.

This Aug. 17, 2015, image, released by Royal Thai Police spokesman Lt. Gen. Prawut Thavornsiri shows a man wearing a yellow T-shirt near the Erawan Shrine before an explosion occurred in Bangkok, Thailand.

No one has claimed responsibility for the bombing, and police say they are considering a range of possibilities, including those involved in the country's long-standing internal political unrest, Muslim insurgents from the country's south, or Uighurs upset at Thailand's decision to deport more than 100 Uighurs back to China last month.